Joint USAF/NOAA Report of Solar and Geophysical Activity 11 May 2012

:Product: Report of Solar-Geophysical Activity
:Issued: 2012 May 11 2200 UTC
# Prepared jointly by the U.S. Dept. of Commerce, NOAA,
# Space Weather Prediction Center and the U.S. Air Force.
#
Joint USAF/NOAA Report of Solar and Geophysical Activity
SDF Number 132 Issued at 2200Z on 11 May 2012
IA. Analysis of Solar Active Regions and Activity from 10/2100Z
to 11/2100Z: Solar activity has been at low levels for the past 24
hours with several C-class x-ray flares. Region 1476 (N10W06) was
the source for nearly all of the reported flares, with the largest
being a C6 that occurred at 11/1738Z. This region has remained
mostly consistent as an Fkc/beta-gamma-delta spot group, but has
shown some signs of decay, mainly in the trailer spots. New Regions
1479 (N15E65) and 1480 (S16W10) were numbered over the last 24
hours, are Hsx/Axx classifications respectively, and have yet to
show much activity.
IB. Solar Activity Forecast: Solar activity is expected to be at
moderate levels with a slight chance for X-class x-ray flares for
the next three days (12 – 14 May) as Region 1476 keeps its
Fkc/beta-gamma-delta configuration.
IIA. Geophysical Activity Summary 10/2100Z to 11/2100Z:
The geomagnetic field has been at quiet to active levels for the past
24 hours. Solar wind measurements, as observed by the ACE
spacecraft, showed a fairly steady drop in speeds from approximately
650 km/s down to approximately 550 km/s. The effects of the coronal
hole high speed stream (CH HSS) should begin to wane over the next
24-48hrs. The total IMF remains fairly stable at approximately 5
nT. The greater than 2 MeV electron flux at geosynchronous orbit
reached high levels during the period.
IIB. Geophysical Activity Forecast: The geomagnetic field is
expected to be at quiet to unsettled levels for days one and two
(12-13 May), then return to quiet levels on day three (14 May).
III. Event Probabilities 12 May-14 May
Class M 75/75/75
Class X 20/20/20
Proton 10/10/10
PCAF Green
IV. Penticton 10.7 cm Flux
Observed 11 May 136
Predicted 12 May-14 May 130/130/130
90 Day Mean 11 May 113
V. Geomagnetic A Indices
Observed Afr/Ap 10 May 011/013
Estimated Afr/Ap 11 May 011/012
Predicted Afr/Ap 12 May-14 May 007/008-007/008-006/005
VI. Geomagnetic Activity Probabilities 12 May-14 May
A. Middle Latitudes
Active 15/10/05
Minor storm 05/01/01
Major-severe storm 01/01/01
B. High Latitudes
Active 20/15/15
Minor storm 25/20/15
Major-severe storm 20/10/05